We continue to live in a dangerous world. We are exposed to the risk that hostile states or terrorist groups with global reach might attack our civilian population or those of our allies using weapons of mass destruction. In such circumstances, it might seem natural for U.S. policymakers to consider preventive war as a possible tool for countering such threats. Yet in the current climate of opinion, such thinking would be controversial - in large part, no doubt, because of the continuing disputes over the normative, strategic, and legal wisdom of what has been called the “Bush Doctrine.”
Preventive war, in appropriate circumstances, can be justified for reasons that are closely analogous to those usually offered to justify humanitarian intervention. The key difference is that in preventive war the intervenors protect their own populations, whereas in humanitarian intervention the intervenors protect the target state’s population. Although critics of preventive war tend to be sympathetic to humanitarian intervention, the underlying logic for both uses of force is substantially the same.
In this Essay, we first explain what we mean by “preventive” war, and how it is distinguishable from “preemptive” war. Then we briefly consider whether, as critics of the Bush Doctrine allege, the War in Iraq was virtually unprecedented in the Nation’s history or was, instead, one of several major conflicts fought by the United States that could fairly be described as preventive wars. Finally, we shall recommend certain normative guidelines and criteria for policymakers to follow in deciding whether to initiate a “preventive” war.